If you thought Carrie Coon was all sweet and Honey, you just haven't yet seen "The Real Thing."

In Michael Halberstam's smart, stimulating and sometimes beguiling production of the 1982 Tom Stoppard play about how smart, stimulating and sometimes beguiling people can have crisis-strewn love lives, this remarkable young actress, one of the most arresting talents to suddenly appear in Chicago in years, achieves one thing above all else. Plying her theatrical trade at Writers' Theatre, where most bedrooms are set well back from the street but many of the denizens are familiar with the art of negotiation, Coon forges an aggressive, dangerously desirable, young woman — one whom a man can never be sure won't one day get up and leave.

Whether this improves, or fatally wounds, one's love life is one of the many topics under debate in this ripe-for-revival play that has lost none of its currency, nor its intellectual and sexual charge.

From my smitten point of view (let's just lay that out), the most prescient worry is that Coon will be seduced by New Yorkers when she reprises her remarkable performance as Honey in "Who's Afraid of Virginia Woolf?" on Broadway next fall and will not return. That was going through my head when Coon's character, a fidelity-challenged actress named Annie, turned to her chap, a playwright named Henry (played by Sean Fortunato) and delivered the line: "You won't let it wear away what you feel about me?"

The "it' under discussion is Annie's inconstancy. Henry's reply is one of the most honest things Stoppard ever wrote: "No," he says, knowing that this reply might well be emasculating his own masculinity, if not his humanity. "It will either go on or it will flip into its opposite."

Who has not been there? To the going-on part. And also, lord knows, to the opposite-feelings part. Of course, the Annies of this world are unmoved. "You have to find a part of yourself where I'm not important," says Coon's flawlessly accented and (thanks to costume designer David Hyman) arrestingly attired Annie, employing just the right blend of vulnerability and ice, of lovable and never-knowable, "or you won't be worth loving."

In essence, the pleasures of "The Real Thing," a play set among the cause-following and arts-loving London cultural classes, flow from watching Stoppard apply the same linguistic and intellectual rigors to marital intimacy that, in other plays ("Arcadia," Rock 'N' Roll") he applies to metaphysics and the disappointments of socialism. Most movies and plays about love and sex are, of course, simplistic and romantic. Not this one. Here, the relationship with which the play is most concerned itself began in adultery. Henry was originally married to Charlotte (in a nicely nuanced and richly textured performance from Natasha Lowe) and Annie to Max (a hapless, malleable John Sanders); the jettisoned Charlotte prospers more than most in this Stoppardian world.

The play's overarching view of commitment is, inarguably, as cynical as Charlotte becomes. Henry and the other men learn that there are only bargains in relationships. Bargains constantly up for renegotiation.

Halberstam's robust and restless production embraces the play's metatheatricality and tricks, with the help of a classy set design from Collette Pollard. Halberstam doesn't fully solve the part of the plot dealing with Annie's relationship with another playwright, Brodie (Ryan Hallahan), a character designed as a repository for Stoppard's less-than-favorable view of oafish, leftist writers. That is a weak spot in the script and it sits uneasily here, as ever.

But Brodie is a minor detour. The main journey here belongs to Henry, and there are times when you want Fortunato to meet Coon more aggressively and reveal his painful inadequacy more deeply. On opening night Thursday, there were roads not yet fully traveled.

But by the time we get to the second act, Henry's fate at the hands of this Annie is, to say the least, terrifyingly familiar. Fortunato is not an actor who comes easily to emotionally revealing choices. Whenever he does, it costs him, and he starts to get really good when you begin to see the price. It is a right-headed performance that will only get better, being dedicated to the real thing.

There are very few plays that make clearer that, whatever one's accomplishments, those accomplishments can be laid to waste by suspicions of a cheating lover or spouse. Especially one that you cannot — should not — let go.